Apparatus and method of turning blanks



, J1me 1957 H. .J. eoss 2,794,372

APPARATUS AND METHOD OF TURNING BLANKS Filed Oct. 15, 1953 a 2 Sheets-Sheet 2 REAR Fowme' MECHANISM FRONT FOLDING MECHANISM Unite APPARATUS AND METHOD OF TURNING LANKS Application October 15, 1953, Serial No. 386,213

18 Claims. (Cl. 93-49) This invention relates to apparatus and methods for making paper boxes from box blanks and especially to apparatus and methods for turning such blanks through an angle of 90 as they progress along the paper line on a folding machine.

It is well known that paper box folding machines are often made up of front and rear folding mechanisms, the front mechanism folding two opposite walls of the box and the rear mechanism folding the other two opposite walls of the box. Sometimes the rear folding mechanism has been set at right angles to the front folding mechanism to permit a blank to be advanced, first with a longitudinal axis parallel to the direction of advance and then with the same axis transverse to the direction of advance. Such right angular machines occupy considerable space so that straight line machines are usually preferred, there being a turning device intermediate of the front and rear folding mechanism for turning each blank through an angle of 90.

Heretofore turning devices have been proposed comprising a fixed turntable, with the blank not advancing as it turns as in Patent No. 2,019,973 issued November 5, 1. 35, to Hormel, and in Patent No. 2,541,414 issued February 13, 1951, to me. It has also been proposed to use a turntable which advances in a straight line as it turns as in Patent No. Re. 18,643 issued May 17, 1932, to me and Patent No. 2,618,207 issued November 18, 1952, to Hery et al. Fixed turntables may tend to slow down the production of the machine because the blank is not advancing along the paper line while it is turning and after the blank is turned, it must be removed to provide space for the next blank. Straight line advancing turntables, on the other hand may tend to require considerable apparatus including endless carriers, supporting plates and the like, all of which may be diflicult to retain in adjustment and position at high speed operationf The principal object of this invention is to provide in a straight line paper box folding machine, a turntable which advances along a rigidly and accurately guided curved path as it turns and then returns along the same path to its initial position.

Another object of the invention is to provide a carrier, in the form of a rigid member so pivoted as to horizontally oscillate a turntable from proximate the front folding mechanism to proximate the rear folding mechanism, thereby rigidly supporting said turntable during its advancement.

Still another object of the invention is to provide an oscillating carrier member for a turntable together with positive drive means for the same in the form of a sun and planetary gear for rotating the turntable during each oscillation.

A further object of the invention is to provide a revolvable platform movable in a curved horizontal path from a point on a straight paper line to a point further advanced on the paper line and a clamping jaw, movable on the same path, for holding a blank on the platform.

A still further object of the invention is to provide a blank turning platform oscillating in a non-rectilinear path alongside the rectilinear central axis of a paper line States Paton t ice together with novel blank positioning means and novel blank extracting means thereby forming an inexpensive, uncomplicated turning apparatus capable of accurate, high speed production.

In the drawings- Fig. 1 is a plan view of the apparatus of this invention with parts broken away for clarity.

Fig. 2 is a side elevation in section on line 2-2 of Fig. 1.

Fig. 2a is a fragmentary view, similar to Fig. 2, of a modified drive mechanism for the oscillating carrier member of the invention.

Fig. 3 is an end elevation in section on line 3-3 of Fig. 1.

Fig. 4 is a fragmentary side view of the blank positioning means of the invention, and

Fig. 5 is a diagrammatic plan view showing the path of advance and turning of blanks in apparatus according to this invention.

In Figs. 1 and 5, a typical blank 20 is shown as illustrative of the type of box 'blank, envelope or similar substantially flat sheet that can be turned by the apparatus and method of this invention. Blank 20 ha a bottom panel 21, a pair of oppositely disposed end walls 22 and 23, a pair of oppositely disposed side walls 24 and 25 and suitable flaps or tabs, creases or score lines all well known in the art and forming no part of the invention herein. 7

In Fig. 5 the location of What I call the front folding mechanism 26 and the rear folding mechanism 27 of the machine is illustrated diagrammatically and it will be apparent that a front portion 28 and rear portion 29 of the paper line P is included in each and that each portion is in rectilinear alignment, or straight line extension with the other. The front and rear folding mechanisms 26 and 27 may be of any well known type and, since the structure thereof forms no part of this invention, they are not illustrated. However, front and rear folding mechanisms 26 and 27 are spaced apart to form what I call a blank turning Zone 30, and it is the apparatu of this invention located in zone 30 that is illustrated in Figs. 1 and 2. Blanks such as 20 are advanced through the front folding mechanism 26 by suitable conveyors wherein they may have adhesive applied to various portions, have two opposite side walls folded or be otherwise acted upon prior to being turned through an angle of Upon delivery of a succession of individual blanks such as 20 t0 the turning zone 39, each blank 20 is received upon a stationary platform 31 which platform preferably extends the full length of the turning zone. 7 Platform 31 is at the level of paper line P and is provided with a longitudinal slot 32 extending along the central longitudinal axis 33 of paper line P, slot 32 being curved at 34 for a purpose to be hereinafter explained. The platform 31 is supported by leg members such as 35, extending upwardly froma rod such as 36, the rod 36 extending transversely of the machine and having each opposite end thereon supported in a side piece 37 or 38 of the frame 39 of the machine. 7

An endless conveyor belt or chain 40 is provided in slot 32 of platform 31, the upper stretch 41 thereof being at the level of the paper line P and the belt 40 being trained around a power pulley 42, supporting rollers such as 43 and idler pulleys such as 44. Each successive blank 20 delivered by front folding mechanism 26 onto platform 31 is engaged by the upper stretch .41 of belt 40 and advanced along the paper line P until it isstopped by the blank positioning means of the invention. Holddown rollers such as 45 are preferably provided above and opposite the belt 40 to assure the advance of each blank 20 on the belt. Rollers 45 are each mounted on a bracket 46'depending from a longitudinally extending frame piece 47, the frame piece 47 being supported on transverse rods 43 and 49 of frame 39.

Blank positioning means The blank positioning means D of the invention is best shown in Fig. 4 and includes a pair of stop fingers such as 51 each located on an opposite side of the central longitudinal axis 33 of paper line P, intermediate of the front and rear folding mechanisms. The stop'fingers 50 are located in turning zone 30 at about the half way point of the curved portion 34- of slot 32 and are spaced apart transversely of the machine a sutficient distance to not obstruct either the straight or the curved portion of slot 32. Each stop finger t) depends downwardly from the terminal end 51 of an elongated rod 52, which rod extends over the approaching blanks, above the paper line P, and is supported near its opposite end 53 by an element 54. Each rod such as 52 is slidable longitudinally in its supporting element 54 and may be fixed in various lengthwise positions by a suitable setscrew 55 to accord with the length of the blank 20. Elements 54 are fixed at spaced distances apart to a transverse shaft 56, the shaft being journalled at each end in bearings such as 57 supported on frame 39. I call the downwardly depending element 54 and the portion of rod 52 extending over a blank 20, an arm 58 and it will be noted that the stop fingers 51} are thereby pivotally mounted to oscillate in an arcuate path in a vertical plane in front of a leading edge 59 of each successive blank. A lever 60 is fixed to transverse shaft 56 at one end and pivotally connected at its other end 61 to a cam follower element 62 having a follower roller 63 and a yoke 64. Yoke 64 partially encircles a collar '65 carried by a power shaft 66, the shaft 66 also carrying a cam 67 the surface of which is in contact with roller 63. A protuberance 68 on cam 67 causes the roller 63 to rise and fall with each revolution of shaft 66 and thereby raises and lowers stop fingers 50 in their curved path. Each stop finger, in synchronization with the other operating mechanism of the machine thus falls into place in front of the leading edge 59 of the leading blank 20 advancing on belt 40 and stops the leading blank momentarily in the correct position to be engaged by the blank turning means of the invention and then rises away from the blank in the direction of advance of the blanks through the machine.

Blank turning means The blank turning meansA of the invention includes a turntable, or revolvable platform, '71 positioned between the front folding mechanism 26 and the rear folding mechanism 27 in the turning zone 30 and at the level of paper line P. As best shown in Fig. 3, the platform 71 is of a diameter to fit within the sides of the curved portion 34 of the slot 32 in stationary platform 31 and preferably includes a circular recess 72 having a cork insert 73 therein. Platform 71 may be of a slightly larger diameter if desired to support a greater proportion of the under surface of a blank 20 but it is preferred that the platform be about the diameter shown since .it is to be oscillated and should not be unwieldy, or heavy. The platform 71 is revolvable by means of an'integral depending shaft 74 journalled in a sleeve 75 and having a sprocket 76 at the lower end of the shaft whereby rotation of the sprocket causes rotation of the platform. Preferably the rotatory mechanism for the revolvable platform 71 is carried by the rigid member 77 of the oscillating carrier means of the invention and is operated by the teeth of what I call a sun gear 78 fixed around the pivot 79 of member 77. The rotatory mechanism includes what I call a planetary gear 80, the teeth of which are enmeshed with the teeth of the non'revolvable sun gear 78. Gear 80 is revolvable on a shaft -81, mounted on the rigid member 77, and a sprocket 821s carried by shaft 81 to revolve with gear :89. A, chain 83 is trained around the pair of sprockets 82 and76 4 so that platform 71 revolves accurately and positively when planetary gear revolves around sun gear 78.

Oscillating carrier means The oscillating carrier means B of the invention includes the rigid member 77, which carries the revolvable platform 71 at its free, or oscillating end, and is pivoted at its opposite end to the frame 39 at pivot 79. As shown in Fig. 3, member 77 includes the sleeve 75 en'- circling shaft 74 and a similar sleeve 84 encircling a vertically positioned pivot pin 85. Pin 85 together with a suitable bushing 70 passes through openings 86 and 87 in arms 88 and 89 of a bracket 90, the bracket being fixed to frame 39 by bolts such as 91. Sun gear 78 is preferably carried by bracket 90, as indicated, and is immovably mounted on an arm such as 89 by welding or other suitable means. vIt should be noted that the parti-circular path of revolvable platform 71 in the arcuate slot 34 and on the rigid member 77 is less than 90 in angular length and that the centre of the particircular path, at pivot 79, is located at a spaced distance sidewise from the straight paper lineportions 28 and 29.

Oscillator mechanism for the rigid member 77 is provided (as best shown in Fig. 2) and includes a rod 92, having one end 93 pivotally connected at 94 to a downward extension 95 of shaft 81. The other end 96 of rod 92 is pivotally connected at 97 to an arm 98 of a bell crank lever 99 and the bell crank lever 99 is pivoted at 1&0 to a transverse shaft 101. The other arm 102 of bell crank lever 99 is pivotally connected at 103 to a roller type cam follower 104 and the cam follower 104 follows an eccentric cam 1G5 mounted on a power shaft 106. Rotation of shaft 106, by means of the above connections, causes the rigid member 77 to carry revolvable platform 71 from the position shown in full lines at 107 in Fig. l to the position shown therein in dotted lines at 138 and then to return to its initial position. The harmonic motion achieved by the cam 105, and follower 104 results in the velocity of the platform 71 being zero at the opposite ends 107 and 103 of its arcuate horizontal path and at a maximum in the center 1199 of the path. In its full line position 107, platform 71 is directly under the center of the undersurface of the bottom panel 21 of a blank 20, which blank has been momentarily stopped by fingers 56 with said center on the central longitudinal axis 33 of paper line P. Carried by rigid arm 77, platform 71 then describes a curved horizontal path, removed from the axis 33 and parallel to the curved slot 34 with gradually increasing acceleration to the mid point 109 thereof and then with gradually increasing deceleration to the dotted line positions 108 shown. In its dotted line position 168 the revolvable platform 71 is again back on the axis 33, at a point further advanced along paper line P in the direction of feeding and is in position for the blank to be picked up and advanced by the blank extracting means of the invention. During its travel along the aforesaid arcuate path the blank such as 29 is turned by the blank turning means A until at the end of the path, the blank is at an angle of 9 to its original position.

As shown in Fig. 2a, I ma oscillate the rigid member 77 of the oscillating carrier means B by means of a rod 192 similar to rod 92 shown in Fig. 2. In place of bell crank lever 99, cam follower 194 and eccentric cam I provide a bell crank lever 199, a yoke type cam follower 204 and an eccentric cam 205 encircled by the yoke follower 204. Lever 199 is pivoted at 2131 on a transverse shaft 207, supported on frame 39, and includes a long arm 198 pivoted to rod 192 at 197 and a short arm 202 pivoted to yoke follower 204 at 203.

Blank clamping -means Blank clamping means C is preferably provided and involves a freely revolvable clamping jaw 116, as best shown in Fig. ,3, which is preferably made of rubber in inverted cup shape. Jaw 110 is positioned above, and

opposite to platform 71 and is preferably carried by the rigid member 77 of the oscillating carrier means B of the invention. An arm 111 is provided, having a sleeve 112 at its free terminal end, the sleeve 112 encircling a freely revolvable shaft 113 which carries the jaw 110 at its lower end 114. Arm 111 is mounted to pivot at 115 in a vertical plane on an upward extension 116 of the shaft 81, the extension 116 being supported on member 77 above the planetary gear 80 and above the downward extension 95 of shaft 81.

A coil spring 117 connects arm 111 with rigid member 77 whereby the jaw 110 is normally held at a spaced distance above platform 71, as on the return trip of the arm 77, and a stud 118 is mounted at the end of arm 111.

Actuating mechanism for arm 111 includes the pivot pin 85, the upper end 119 thereof being aligned with stud 118 and the lower end 120 thereof being in contact with a lifter arm 121. Pivot pin 85, is vertically slidably within the sleeve-like bushing 70 and when pin 85 is lifted upward by arm 121 it causes the downward oscillation of jaw 16 into contact with a blank such as 20 supported on platform 71 thereby clamping the blank in position for turning with the platform and for advancement on carrier means B. As indicated in Fig. 2, lifter arm 121 is pivoted at 122 to a transverse shaft 123 and its opposite end 124 carries a cam roller 125. Roller 125 is in contact with the surface 126 of cam 127 mounted on power shaft 106 and therefore is synchronized with the oscillations of the rigid member 77. Thus, jaw 110 is lowered into contact with a blank as soon as the blank is stopped by fingers 54), then holds the blank tightly on platform 71 as the platform 71 is turned and advanced and then is raised from contact with the blank at the end 198 of the path of platform 71. It remains in the upward position during the return oscillation of rigid member 77 and then repeats the above cycle. A coil spring 128 is provided to return the arm 121 and to maintain cam follower roller 125 in contact with cam 127.

Blank extracting means The blank extracting means E of the invention is best shown in Figs. 1 and 2 and includes a pair of conveyor belts 138 and 131 oppositely disposed above and below paper line P. Means E is positioned to receive a blank such as 213, after the blank has been turned by blank turning means A and simultaneously advanced by oscillating carrier means B to point 168 on paper line P. The lower conveyor belt 131 is trained around a drive pulley 132, mounted on a power shaft 133, and is also trained around a fixed idler pulley 134 whereby the upper stretch 135 of belt 131 is at the level of the paper line. The upper conveyor belt is trained around a pulley 136, carried by a power shaft 137 and is also trained around idler pulley 138 whereby its lower stretch 139 is also at the level of paper line P.

A rocker arm 149 is provided, mounted on a transverse shaft 141, and having an arm 143 which carries the idler pulley 138 of upper belt 130.

A roller 144 is carried at the end of the other arm 145 of rocker arm 140 and is in contact with the surface of a cam 145 mounted on shaft 137. Coil spring 147 is arranged to maintain roller 144 in contact with cam 146.

With each revolution of cam 146, the protuberance 149 on its surface, depresses roller 144 thus raising idler pulley 138 away from idler pulley 134. I call the nip between idler pulleys 138 and 134, the entrance nip 150 of blank extracting means E and it will be noted that the entrance nip 150 is expandable and contractable as indicated in dotted lines. I call pulley 136 the rear upper pulley, pulley 132 the rear lower pulley, pulley 138 the front upper pulley and pulley 134 the front lower pulley. As shown in Fig. 1 the point 108, at the end of the horizontal arcuate path of platform 71 is on the central longitudinal axis 33 of paper line P and just in front of entrance nip 150. The nip 1513 opens, or expands, in Synchronization with the other parts of the machine to receive the leading portion of the blank, on platform 71, and then closes thereon, as clamping means C releases the blank. The closing of nip 150 causes the conveyor belts 130 and 131 to draw the blank, such as 20, off platform 71 and to continue its straight line advancement into the rear folding mechanism 27.

Operation The power shafts 66 of blank positioning means D, power shaft 106 of oscillating carrier means B and blank clamping means C and the power shafts 133 and 137 of blank extracting means E are all synchronized in a manner well known in the trade to cooperate with the front and rear folding mechanisms 26 and 27 and blank tuming means A, through sun gear 78 and planetary gear is positively and accurately operated by oscillating carrier means B.

A plurality of blanks such as 20 are advanced through front folding mechanism 26, individually and successively, and the centre of each blank follows the rectilinear central longitudinal axis 33 of paper line P. Each successive leading blank is contacted along its leading edge by stop fingers 50 and halted momentarily with its centre directly over revolvable platform 71. The freely revolvable clamping jaw 110 closes down into engagement with the upper surface of the blank and stop fingers 50 immediately rise out of the path of the blank. Rigid member 77 then moves the blank 20, supported on platform 71 and clamped by jaw 110, along a horizontal arcuate path parallel to slot 34 in platform 31 while the remainder of the blank is supported on platform 31. As the platform 71 and jaw 110 move, planetary gear 80, turns the blank until at the end 108 of the path, blank 20 is at an angle of to its initial position.

Entrance nip 150 opens to receive the blank 20 and closes on the blank immediately upon its arrival at point 108 while jaw simultaneously releases the blank. Conveyor belts and 131 then continue the advance of the blank 20 to the rear folding mechanism 27 along rectilinear axis 33 of paper line P while rigid member 77 returns to turn the next succeeding blank.

I claim:

1. A box blank folding machine having front and rear folding mechanisms, each having a portion of a horizontal paper line of the machine in rectilinear alignment with the other; blank turning means, including a revolvable platform and rotatory mechanism therefor, said platform being positioned between said front and rear folding mechanisms at the level of said paper line for turning a blank in the plane of said paper line partially around a centre of rotation within the blank; and oscillating carrier means including'a rigid member pivoted at one end to said machine and carrying said platform, at its other end, for successively advancing said platform from the paper line of the front folding mechanism to the rectilinearly aligned paper line of the rear folding mechanism along a horizontal arcuate path at the level of said paper line.

2. A machine as specified in claim 1 wherein said rotatory mechanism is carried by the rigid member of said oscillating carrier means, for turning said platform.

3. A machine as specified in claim 1 wherein said rotatory mechanism includes a planetary gear, carried by the rigid member of said oscillating carrier means for positively turning the revolvable platform of said blank turning means.

4. A machine as specified in claim 1 wherein said oscillating carrier means comprises said pivoted rigid member and oscillator mechanism, including a harmonic motion cam and bell crank lever cam follower synchronized with said front and rear folding mechanisms, for

swingably moving said rigid member on its pivoted end, with zero velocity at each'opposite end of its path and maximum velocity at the centre of its path.

5. A machine as specified in claim 1 wherein said rotatory mechanism includes a planetary gear, carried by said rigid member, for positively turning said platform and a sun gear immovably mounted proximate the pivoted end of said rigid member for positively turning said planetary gear.

6. A machine as specified in claim 5 wherein said rotatory mechanism also includes a pair of sprockets and a chain carried by said rigid member and interposed as a drive connection between said planetary gear and said revolvable platform.

7. A machine as specified in claim 1 plus blank clamping means, including a freely revolvable clamping jaw positioned above, and opposite to, said revolvable platform, and carried by the rigid member of said oscillating carrier means for retaining a blank on said platform.

8. A machine as specified in claim 1 plus blank clamping means, said means including a freely revolvable clamping jaw, positioned above and opposite to said revolvable platform; an arm supporting said jaw and mounted to pivot in a vertical plane on the rigid member of said oscillating carrier means, and actuating mechanism, cooperable with said oscillating carrier means, for pivoting said arm and thereby raising and lowering said clamping jaw.

9. A machine as specified in claim 1, plus blank positioning means, including a pair of stop fingers, each on an opposite side of the central longitudinal axis of the paper line of said machine intermediate of said front and rear folding mechanisms and a pair of longitudinally extending rods, each having a free terminal end supporting one of said fingers, said rods being pivotally mounted on said machine to oscillate said fingers in an arcuate path in a vertical plane in front of each successive blank for stopping said blank on said paper line with the centre of said blank in position to be engaged by the platform of said blank turning means.

10. A machine as specified in claim 1 plus blank extracting means mounted on said machine in position to receive the leading edge portion of a blank, after said blank has been turned by said blank turning means and advanced by said carrier means, said blank extracting means including an upper and lower blank conveyor belt uniformly spaced from each other having an expandable and contractable entrance nip proximate the rear folding mechanism end of said arcuate path for opening to receive the leading edge portion of a turned blank and closing to convey said blank to said rear folding mechanism.

' 11. A machine as specified in claim wherein said blank extracting means comprises a pair of oppositely disposed upper and lower blank conveyor belts each having a front pulley and a rear pulley; a cam mounted to revolve with the rear pulley on said upper belt, and a rocker arm, pivoted to said machine between the front and rear pulleys on said upper belt, one end of said rocker arm carrying said front upper pulley and the other end of said rocker arm including a cam follower in contact with the cam on said rear upper pulley whereby each revolution of said rear upper pulley and cam causes said rocker arm to move the front upper pulley toward and away from the front lower pulley of said belts.

12. A box blank folding machine having front and rear folding mechanisms, each having a portion of a horizontal paper line of the machine in rectilinear alignment with the other, blank positioning means for stopping the advance of .each successive blank received from saidfront folding mechanism, on said paper line in position to be turned; blank turning means including a revolvable platform for supporting the centre of the lower surface of each said stopped blank and rotatory mechanism for turning said platform through an angle of blank clamping means including a freely revolvable clamp ing jaw, cooperable with said blank turning means, for si-' multaneously clamping the upper surface of each said blank against the platform of said blank turning means; oscillating carrier means including a rigid arm pivoted alongside ,said paper line and supporting both said blank-turning means and said blank clamping means, for advancing the same along a horizontal arcuate path emending from said blank positioning means to blank extracting means in the direction of feeding, during the turning of each blank, and blank extracting means, at the .end of said arcuate path proximate the rear folding mechanism for engaging each turned blank and delivering the same to said rear folding mechanism.

13. Apparatus for turning box blanks as said blanks are advancing individually and successively along a hori zontal, rectilinear, paper line of a folding machine, said apparatus comprising blank positioning means for stopping each successive blank on said rectilinear paper line in position to be turned; blank turning means including a revolvable platform and rotatory mechanism therefor for turning each stopped blank on a centre of rotation, within the axis of the blank, through an angle of 90; oscillating carrier means including a rigid arm pivoted to said machine alongside said paper line and supporting the revolvable platform of said blank turning means for moving said platform in a parti-circular path at the level of said paper line in the direction of advance of said blanks during said turning, and blank forwarding means for forwarding each turned blank from said blank turning means and continuing the advance of the same along said rectilinear paper line.

14. Apparatus as specified in claim 13 wherein the rotatory mechanism of said blank turning means is actuated by the oscillating motion of said oscillating carrier means.

' 15. The method of turning a flat box blank advancing in a straight line, thru an angle of 90 and then continuing the advance of said blank in said straight line which method comprises the steps of halting said blank momentarily on said straight line, then turning said blank through an angle of 90 on a vertical axis disposed centrally of the confines of the blank while simultaneously advancing the blank along a circular arc to a point further advanced on said straight line, and then resuming the advance of said blank on said straight line.

'16. A method as specified in claim 15 wherein said circular arc is less than 90 angularly in length.

17. A method as specified in claim 15 wherein the centre of the circle partially defined by said are is at a spaced distance sidewise from the straight line path of said blank.

18. A device for individually and successively turning sheets while said sheets travel through a straight line folding machine, said device comprising a rigid arm having one end pivoted to said machine beside the path of travel of said sheets and having a free terminal portion oscillatable in a horizontal plane just below the path of travel of the centre points of said sheets through said machine, means for oscillating said arm forwardly and rearwardly of said machine in synchronization with the travel of said sheets, a pair of oppositely disposed rotatable clamping members supported on the free terminal portion of said rigid arm and adapted to temporarily grip the centre of a sheet therebetween and turning means, associated with said rigid arm, for rotating said clamping members on a vertical axis passing through said arm during each forward and rear oscillatory movement thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,765,419 Goss June 24, 1930 2,016,462 Stokes Oct. 8, 1935 2,541,414 Goss Feb. 13, 1951 

